Fluidic dishwasher spray system

ABSTRACT

In the preferred form this invention teaches a dishwasher including a cavity in which dishes are washed, a plurality of stationary spray nozzle groupings arranged in the washing cavity, and a washing fluid supply system to the nozzle groupings, including at least one fluid logic element arranged to sequentially supply washing fluid to the different nozzle groupings.

United States Paten 1191 Camprubiet al. 1 1

11 1 3,708,120 1 1 Jan.2,1973

1541 FLUIDIC DISHWASHER SPRAY SYSTEM [75] Inventors: BartholomewCamprubi, lckenham;

Grahame Gerald Capron-Tee, Marlow, both of England [73] Assignee: TheHoover Company, North Canton,0hio

[22] Filed: April 6, 1971 [21]' Appl. No.: 131,723

52 us. (:1. ..239/66, 239/536, 239/563, 134/56 D, 137/815 51 int. c1...B05b 13/02 58 Field 61 Search ..239/66, 67, 536, 562, 563, 239/564,569; 134/191, 176, 179, 56 D, 56 R [56] References Cited UNITED STATESPATENTS 3,620,050 11/1971 Glasgow ..137/8l.5 X 1,889,858 12/1932 Greeneet al ..'...239/66 2,596,693 Karlstrom ..134/56 D 3,373,905 3/1968Laufer ...l37/81.5 X 3,447,752 6/1969 Hardy ...137/81.5 X 3,513,8665/1970 Boothe et al. ..137/81.5

' FOREIGN PATENTS OR APPLICATIONS 1,052,349 12/1966 Great Britain..137/81.5 1,920,575 11/1970 Germany ..134/179 Primary Examiner-M.Henson Wood, Jr. Assistant Examiner-John J. Love Attorney-Alfred G.Gross and James A. Wanner [57] 1 ABSTRACT In the preferred form thisinvention teaches a dishwasher including a cavity in which dishes arewashed, a plurality of stationary spray nozzle groupings arranged in thewashing cavity, and a washing fluid supply system to the nozzlegroupings, including at least one fluidlogic element arranged tosequentially supply washing fluid to the different nozzle groupings.

4 Claims, 4 Drawing Figures FLUIDIC DISHWASHER SPRAY SYSTEM Thisinvention relates to washing machines and in particular to a dishwashingmachine. This invention is particularly beneficial in providing asequential fluid discharge operation through a plurality of stationarysupply nozzle groupings in the washing chamber of a dishwasher whileusing a limited amount of washing fluid and utilizing a limited sizepump.

This invention is also beneficial in that the water supply system has aminimum wear and maintenance in that relatively few moving parts areutilized to provide a sequential supply of washing fluid to differentspray nozzle groupings.

Many dishwashers utilize rotary spray arm systems to provide spray intodifferent zones within a cavity in which the dishes are washed. Adisadvantage of these systems is that the spray arms are mounted forrotary or reciprocating movement, therefore requiring many moving partsinvolved which are susceptible to wear. A rotary spray arm system hasthe advantage, however, of using a limited power and water supply systemin that only a part of the cavity is being supplied with washing fluidat any one time.

Given unlimited power it is possible to eliminate the movement of sprayarms by distributing the washing liquid through a plurality ofstationary spray nozzles so as to sufficiently provide washing fluid atall zones within the washing cavity. This not only requires considerablymore power but also requires a greater supply of washing fluid.

It is possible to reduce the power requirement and washing fluidquantity requirement in a fixed spray system without using a rotaryspray arm, but this generally has required the use of a plurality ofmechanically or electrically operated valves which again involves movingparts which are expensive and susceptible to malfunction and thereforecreate maintenance problems.

According to the present invention, a washing machine including a cavityin which dishes are washed is provided with a plurality of stationaryspray nozzle groupings, these groupings being provided with a sequentialwashing fluid supply. The washing fluid supply system includes at leastone, and preferably a plurality of fluid logic devices fed from a commonsource to provide the sequential supply of washing fluid to thedifferent spray nozzle groupings.

The advantage of such a system is that a limited power supply and alimited washing fluid quantity can be utilized in that only a limitednumber of spray nozzles are in operation at any one time. Furthermore,the water supply system provides this feature using simpleinexpensiveelements having no moving parts and thus greatly reducesmanufacturing costs and maintenance problems.

Various fluid logic elements may be incorporated. In the preferred formof the invention which is envisioned, a cascade fluid logic system isutilized whereby each spraynozzle grouping has a fluid logic elementwith Another advantage of the present invention is that the fluid logicelements may be so arranged so as to provide a spray pattern withrelatively even fluid distribution throughout different washing zoneswithin the washing cavity. In the alternative, this system may also bearranged so as to provide different spray pressures within the differentwashing zones within the cavity. This latter feature is provided by thecascading of the fluid logic elements.

Thus, the present invention teaches a washing fluid supply system for adishwasher and a spray nozzle groupings within the washing cavityutilizing simple, inexpensive elements having no moving parts and yetrequiring only a limited power supply and limited supply of washingfluid.

In the drawings:

FIG. 1 is a fragmentary elevational view showing a dishwasher utilizingthe washing fluid supply arrangement of the present invention;

FIG. 2 shows a cross-sectional view of the dishwasher taken along thelines 2-2 of FIG. 1, showing a typical spray nozzle arrangement;

FIG. 3 shows an enlarged view of the fluid control system utilized tosupply washing fluid to the spray noz zle arrangement of FIG. 2; and

FIG. 4 shows a modification of the fluid supply control-system which mayalso be used to supply washing fluid to the spray nozzle arrangement ofFIG. 2.

In the preferred form, the present invention may be carried out in adishwashing machine such as that generally shown in FIG. 1. Thedishwashing machine has a cabinet 2 which generally defines an internalwashing cavity 3 into which dishes and other articles to be washed areplaced. These articles can be arranged on racks 4 and 5 located withinthe washing cavity 3. These racks may be removable through accessopening 6 normally closed by a door 7.

As shown in FIGS. 1 and 2, the dishwasher is provided with a sump 8having a filter 19 which feeds a motor-driven pump 9 which are includedin the preferred form to provide a recirculating spray of water forwashing articles within the cavity 3. Water may be supplied to thewashing cavity by any conventional manner, such as a water supply hosecontrolled by solenoid valves (not shown).

The dishwashing machine may be provided with a conventional timer andcontrol knob generally indicated by 10 which controls the flll solenoidand pump for timed operation.

As shown in FIG. 2 the floor ll of the washing cavity is provided withfour stationary spray nozzle groupings 12, 13, 14 and 15. Each of thesestationary spray nozzle groupingscontain four spray nozzles 18 whichare,

generally aimed upwardly into the washing cavity. It is within theintent of the present invention to' utilize fewer or more spray nozzleslocated solely within the cavity floor or arranged elsewhere within thecavity such as on the sides and top thereof.

Each of these groupings 12, 13, 14 and 15 contains a separate feed lineconnected to the spray control unit 16 supplied from a common centralsource such as the pump 9. A washing fluid under pressure issequentially fed to the stationary spray nozzle groupings by the spraycontrol unit 16 which contains at least one fluid logic element, such aselements 20, 30 and4 0.

The spray control unit 16 is shown enlarged in H0. 3. Pressurizedwashing fluid leaving the pump 9 enters the spray control unit through aconduit 17. Directly fed by the conduit 17 is inlet 21 of the firstfluid logic element 20. The fluid logic element 20 is also provided withtwo outlets 22 and 23. The first of these outlets 22 feeds thestationary spray nozzle grouping 12 through conduit 24. Also provided isa feedback line 25 interconnecting the conduit 24 with a first controlport 26 within the fluid logic element. The fiuid logic element is alsoprovided with a second control port 28 whose purpose will be laterexplained.

The other outlet 23 of the first fluid logic element 20 is connected bymeans of conduit 27 to the inlet 31 of the second fluid logic element30. This fluid logic element 30 is provided with outlets 32 and 33. Theoutlet 32 supplies a conduit 34 which feeds the second stationary spraynozzle grouping 13. Also associated with this fluid logic element 30 isa feedback line 35 interconnecting the conduit 34 and a first controlport 36 of the fluid logic element 30.

The second outlet 33 feeds a conduit 37 which is connected to the inlet41 of the third fluid logic element 40.- Again, this fluid logic element40 has two outlets 42 and 43. The outlet 42 feeds a conduit 44 to supplythe stationary spray grouping 14. A feedback line 45 interconnects theconduit 44 with a first control port 46 of the fluid logic element 40.The outlet 43 feeds a conduit 47 associated with spray nozzle grouping15. Alsoassociated with the outlet 43 and the conduit 47 is a feedbackline which is associated with the second control port 28 of the firstfluid logic element 20.

It is noted that the spray control unit 16 as above described containsno electrical or mechanical moving parts. However, this control unit cansequentially supply washing fluid to the four stationary spray nozzlegroupings 12, l3, l4 and as will now be described.

Washing fluid may be supplied to the cavity 3 through a conventionalmeans not shown. Once a sufficient amount of washing fluid has beensupplied the timer 10 may start operation of the motor-driven pump 9 soas to draw the washing fluid from the sump 8 and thus feed conduit 17.Pressurized washing fluid will enter the fluid logic element throughinlet 21. The washing fluid will leave the fluid logic element 20through outlet 22 and conduit 24 to feed the first spray nozzle grouping12.

Once sufficient pressure has been provided to conduit 24 and also thefeedback line 25, the feedback will act at the first control port 26 soas to switch fluid flow from outlet 22 to outlet 23 so as to feed thefluid logic element 30 through conduit 27. The fluid logic element 20and all the other fluid logic elements herein described are bistable orflip-flop fluid logic elements.

The fluid flow through the second fluid logic element 30 will first feedthe fluid spray nozzle grouping 13 through outlet 32 and conduit 34until sufficient pressure is developed in feedback line 35 and controlport 36 so as to switch fluid flow to outlet 33..The outlet33 feeds thethird fluid logic element 40 through conduit 37 and inlet 41. v

The fluid flow through the fluid logicelement 40 will feed thestationary spray nozzle grouping l4'through conduit 44 until sufficientpressure is developed in feedback 45 and control port 46'so as to switchthe fluid flow through outlet 43 and conduit 47 so as to feed the laststationary spray nozzle grouping 15.

When sufficient pressure has been developed in conduit 47 and thereforefeedback line 49, this pressure will act at the fluid control port 28 ofthe first fluid logic element 20 so as to again provide flow through theoutlet 22. The first fluid logic element will provide flow through line23 until sufficient pressure has been developed at the second controlport 28 since the fluid logic elements are bistable.

This process will be continued in a repeated fashion so as tosequentially feed the stationary spray nozzle groupings l2, l3, l4 and15 until the timer stops the pressurized fluid flow through conduit 17by de-activating the motor-driven pump 9.

It should be noted that the fluid logic elements as shown in FIG. 3 andabove described are cascaded or connected in series relationship. Sincethere is a certain pressure loss through each fluid logic element, agreater pressure will be provided at the outlets of fluid logic element20 than is provided at the outlets of fluid logic elements 30.Furthermore, greater pressure will be provided at the outlets of fluidlogic element 30 than the outlets of fluid logic element 40. Therefore,the fluid pressure at the spray nozzle groupings 14 and 15 will be lessthan the pressure at spray nozzle grouping 13 which will be less thanthe pressure at the spray nozzle grouping 12.

This is provided due to the series relationship of the fluid logicelements and is desirable if the dishwashing machine is designed so asto have higher spray pressures within certain washing zones than theother washing zones. This might be desired if pots and pans are placedin an area above the spray nozzle grouping 12 which could be called ahigh pressure zone. More fragile articles, such as china, could beplaced in an area over the spray nozzle groupings 14 and 15 which couldbe called a low pressure zone.

A modification of the spray control unit 16 shown in FIG. 3 is shown inFIG. 4 and indicated as spray control unit 16. The spray control unit 16is also provided with a conduit 17 connected to the pump 9. A firstfluid logic element 50 is fed from the conduit 17 through inlet 51.Element 50 has two outlets 52 and 53 which feed two other fluid logicelements and 70 through conduits 54 and 55 respectively. Also associatedwith the fluid logic element 50 are first and second control ports 56and 57.

The second fluid logic element has an inlet 61 associated with theconduit 54 of outlet 52 of the first fluid logic element 50. The fluidlogic element 60 has outlets 62 and 63 associated with conduits 64 and65 which feed the stationary spray nozzle groupings l2 and 13respectively.

Also associated with conduit 64 is a feedback line 66 connected to acontrol port 67 of the second fluid logic element 60. Associated withconduit 65 and connected to the first control port 56 of the first fluidlogic element 50 is a feedback line 68.

A third fluid logic element 70 has an inlet 71 in communication withconduit 55 fed by the second outlet 53 of the fluid logic element 50.The fluid logic element 70 has outlets 72 and 73 which feed conduits 74and 75 so as to supply washing fluid to the stationary spray nozzlegroupings 14 and 15 respectively. Associated with the conduit 74 and acontrol port 77 is a feedback line 76. Associated with conduit 75 andthe second control port 57 of the fluid logic element 50 is a feedbackline 78.

The washing fluid control unit 16' operates along the same general linesas the control unit 16 in that it utilizes no electrical or mechanicalmoving parts but is able to provide a sequential fluid supply to thestationary spray nozzle groupings. However, in the modification 16 thetwo fluid logic elements 60 and 70 associated with the spray nozzlegroupings are in parallel relationship with each other and in seriesrelationship with the fluid logic element 50. Again, bistable orflipflop fluid logic elements are utilized to provide the sequentialspray pattern. The operation of the spray unit 16' will now bedescribed.

Pressurized washing fluid provided through conduit 17 will enter thefluid logic element 50 through inlet 51 and leave through outlet 52 andconduit 54 to feed the fluid logic element 60 through inlet 61. Thewashing fluid will then leave the fluid logic element 60 through outlet62 and conduit 64 to feed the spray nozzle grouping 12 until sufficientpressure is developed in feedback line 66 and control port 67 so as toswitch the fluid flow through outlet 62 to outlet 63.

The fluid flow will then leave the fluid logic element 60 through outlet63 and conduit 65 to provide a washing fluid supply to spray nozzlegrouping 13 until sufficient pressure is developed in feedback line 68and the first control port 56 of the fluid logic element 50. At thispoint the fluid flow through fluid logic element 50 is switched fromoutlet 52 to outlet 53 so as to feed the third fluid logic element 70through conduit 55. The fluid logic element 70, in a similar manner tothe element 60, provides fluid supply through outlets 72 and conduits 74to the spray nozzle grouping 14 until sufficient pressure is developedin feedback 76 and port 77 so as to switch the fluid flow from outlet 72to outlet 73.

Fluid flow will now be provided through outlet 73 and conduit 75 so asto feed spray nozzle grouping 15 until sufficient pressure is developedin feedback line 78 and the fluid control port 57 of the first fluidlogic element 50. At this point the fluid flow through fluid logicelement 50 will be switched from outlet 53 to outlet 52, so as to againprovide washing fluid to the fluid logic element 60.

This will be continued in a repeated fashion so as to provide sequentialswitching of the washing fluid to the spray nozzle groupings l2, l3, l4and 15 until operation of the pump 9 has ceased.

It is noted that in this arrangement that the two fluid logic elements60 and 70 which feed the spray nozzle groupings l2, l3, l4 and 15 are inparallel relationship to each other and in series relationship with thefluid logic element 50. Thus, a substantially equal fluid pressure willbe provided through the outlets 62, 63, 72 and 73 so as to providerelatively equal spray pressure at the four stationary supply nozzlegroupings.

It is noted that the spray control units 16 and 16' use fluid logicelements and associated feedback lines to provide the sequential controlof the washing fluid. The feedback control elements automatically switchthe washing fluid from one spray nozzle grouping to another after apredetermined spray period.

If it is desirous to lengthen the predetermined spray period, it may beadvantageous to associate a suitable fluid resistance or capacitatordelay arrangement known in the fluid logic element art with each of thefeedback lines.

As shown in FIG. 2 each of the spray nozzle groupings is provided withfour stationary spray nozzles. This is merely shown to indicate onearrangement of the spray nozzles. Spray nozzles could also be located onthe sides and top of the washing cavity. Furthermore, if it is desired,only one spray nozzle need be provided for each spray nozzle grouping.If a greater or lesser number of spray nozzle groupings are desired, anappropriate number of fluid logic elements must be provided accordingly.

The foregoing is but the preferred forms of practicing the presentinvention. The invention is not limited to the particular details ormodifications shown and described. It is, therefore, intended that theclaims below will cover all modifications which will occur to thoseskilled in the art and do not depart from the scope and spirit of theinvention.

We claim:

1. A washing machine comprising a cabinet defining a cavity for washingarticles, a plurality of spray nozzle groupings each having at least onespray nozzle within said cavity, and a washing fluid spray system forsequentially providing a supply of washing fluid to said spray nozzlegroupings, said washing fluid supply system comprising a pressurizedfluid source, a plurality of fluidic logic elements, a first spraynozzle grouping associated with one of said fluidic logic elements,another spray nozzle grouping associated with another fluidic logicelement, and a feedback circuit interconnecting at least two of saidfluidic logic elements, whereby said interconnection between saidfluidic logic elements causes automatic switching of said fluid supplyto said other spray nozzle grouping upon a sufficient rise of fluidpressure in said first fluidic logic element causing control pressurethrough said feedback circuit.

2. A washing machine comprising a cabinet defining a cavity for washingarticles, a plurality of spray nozzle groupings each having at least onespray nozzle within said cavity, and a washing fluid supply system forsequentially providing a supply of washing fluid to said spray nozzlegroupings, said washing fluid supply system comprising a pressurizedfluid source and a plurality of fluidic logic elements connected in aseries relationship, each of said fluidic logic elements having at leastone output, and an output of each of said fluidic logic element in saidseries relationship being in direct fluid flow connection with at leastone of said spray nozzle groupings.

3. The washing machine of claim 2 wherein a feedback circuit is providedinterconnecting at least two of said fluidic logic elements so as toprovide stepped sequential supply of washing fluid to different spraynozzle groupings.

4. The washing machine of claim 2 wherein said cavity defined by saidcabinet is provided with a plurality of washing zones, each of saidspray nozzle groupings providing a spray pattern in at least one of saidwashing zones whereby different fluid pressures are provided indifferent zones.

1. A washing machine comprising a cabinet defining a cavity for washingarticles, a plurality of spray nozzle groupings each having at least onespray nozzle within said cavity, and a washing fluid spray system forsequentially providing a supply of washing fluid to said spray nozzlegroupings, said washing fluid supply system comprising a pressurizedfluid source, a plurality of fluidic logic elements, a first spraynozzle grouping associated with one of said fluidic logic elements,another spray nozzle grouping associated with another fluidic logicelement, and a feedback circuit interconnecting at least two of saidfluidic logic elements, whereby said interconnection between saidfluidic logic elements causes automatic switching of said fluid supplyto said other spray nozzle grouping upon a sufficient rise of fluidpressure in said first fluidic logic element causing control pressurethrough said feedback circuit.
 2. A washing machine comprising a cabinetdefining a cavity for washing articles, a plurality of spray nozzlegroupings each having at least one spray Nozzle within said cavity, anda washing fluid supply system for sequentially providing a supply ofwashing fluid to said spray nozzle groupings, said washing fluid supplysystem comprising a pressurized fluid source and a plurality of fluidiclogic elements connected in a series relationship, each of said fluidiclogic elements having at least one output, and an output of each of saidfluidic logic element in said series relationship being in direct fluidflow connection with at least one of said spray nozzle groupings.
 3. Thewashing machine of claim 2 wherein a feedback circuit is providedinterconnecting at least two of said fluidic logic elements so as toprovide stepped sequential supply of washing fluid to different spraynozzle groupings.
 4. The washing machine of claim 2 wherein said cavitydefined by said cabinet is provided with a plurality of washing zones,each of said spray nozzle groupings providing a spray pattern in atleast one of said washing zones whereby different fluid pressures areprovided in different zones.